The simplest versions would include vocabulary work in the context of the reading of the unit, or a few grammar mini-lessons and practice during proofreading of a writing assignment. (Choose grammatical problems most likely to come up with the kind of writing you’re assigning.) Spelling instruction and tests are language instruction (orthography). However, language lessons might also include lessons about dialects, word origins, language history, how to get better sentence variety in writing, comparison of authors’ writing styles, analysis of stylistic elements such as diction and syntax, or purposeful misuses of language to achieve humor (malapropisms or puns) or to achieve a political goal (Double Speak). Particularly with writing, remember not just to command and grade proficient use of language; teach students how to do it successfully. (Thanks to Bruce Robbins for this Explanation)
(Thanks to Bruce Robbins for this Explanation)